In my copending U.S. patent application Ser. No. 889,029, I show and describe a low cost solar energy collector using a blackened fly screen chamber enclosing a space through which air arises upwardly, carrying heat with it into a sheltered structure collected solar heat. The invention in Ser. No. 889,029 is shown as part of a wall of a building, situated between two upright posts carrying a roof structure, said posts resting on under ground footings.